With a few well-thought-out changes, an architect and a designer enhance their 19th-century Cape inside and out.

MICHAEL DOHERTY AND NANCY HACKETT DID MORE than update their 1856 Cape to suit their vision of 21st-century family life: They celebrated the house's style, history, and livability. They also made a good location better by taking advantage of the view across the road and down a public way to Beverly's Mackerel Cove.

"We had a Martha's Vineyard fantasy," says Hackett, co-director of the interior design program at New England School of Art & Design at Suffolk University. "We wanted to sit and look at the ocean, watch the boats coming and going, and wave to passersby. We didn't want to add space; we wanted to change how the house lived."

The design that Hackett and her husband, a senior associate principal architect at ADD Inc in Cambridge, came up with did just that. The renovation, done on a budget of less than $100,000, features a mahogany porch that wraps around two sides of the 2,200-square-foot house, an upstairs deck with modern railings made of marine cable off the master bedroom, and a wide shed-roofed addition to the second floor that replaces two small doghouse dormers. Now the interior is full of light, there are new outdoor living spaces, and the house itself is pleasantly handsome. And these improvements neither diminish nor fight with the historic character of the 19th-century survivor.

"We are both Modernists," Doherty says, "I'd never design a Colonial house. But we love this house for the view, so I designed a contemporary addition to fit the vernacular."

Developed on Cape Cod in the 1700s, the sensible, unassuming Cape-style house never went out of style in New England. Unfortunately, say Hackett and Doherty, today's homeowners and builders are often blind to the abiding charms of Cape Cod houses and tear them down or overwhelm them with monstrous additions.

"It's a cultural phenomenon: bigger and worse," Doherty says.

"And then there's the tear-down phenomenon," his wife adds. "It's crazy. We have to push for sustainability."

" This is a small, modest house," Doherty says, "but it's a pretty little house by the sea. You don't know how many people walk across the lawn to tell us that they love it."

In 1994 and '95, shortly after Doherty and Hackett bought the house - which they share with their two children, Tamsin, 15, and Graham, 11 - they replaced the outdated kitchen. Though the three bedrooms were upstairs, the home's only decent bathroom was on the first floor, so two years after the kitchen project, they gutted an antiquated and dilapidated bath on the second level and started over. This latest renovation, completed earlier this year, finished their plans for what they call "a casual house, a beach house."

"At the end of a workday," says Hackett, who is also an assistant professor in the interior design program at Suffolk, "it's nice to come home to the North Shore and to feel close to the ocean. More space would have been nice, but our budget was limited. So instead of a big new master suite, we have this!"

The new, continuous porch makes the most of the house's proximity to the water. Its longer leg functions as an entry porch and, at 7 feet wide, is deep enough to comfortably accommodate groupings of chairs.

The shorter, ocean-facing side of the porch on the house's gable end is 10 1/2 feet deep and functions as an outdoor room accessible from the living room via three new French doors. The porch roof creates summer shade on the house's south side, while the doors on the ocean side of the porch encourage breezes to flow through the house.

"The porch and its roof make the interior 10 degrees cooler in the summer and an equal amount warmer in the winter," says Doherty, noting that "in the winter, the sun is low, and light streams in through the French doors."

The doors repeat the two-over-two glazing of the original windows; Doherty's paired porch columns provide another subtle echo of original design elements.

The gable end facing the ocean also got a new sunroom off the living room, where a screened porch previously had been. The room, which the family uses as a library, also has a French door that opens onto the new porch.

Rooms are furnished simply in warm neutrals and earth tones.

"The interior design grew out of the architecture," Hackett says. "I have a good eye for color and form, but not a big budget."

"It's fun, colorful, bright!" says her husband.

"Good architecture should be a public service," Doherty says, taking evident satisfaction in the way neighbors have embraced the new design.